Diagnostic Agreement between Clinicoradiological and Histopathological Diagnosis in Interstitial Lung Disease: A Cross-sectional Study at a Tertiary Care Center

Background: Interstitial lung diseases (ILDs) have a wide spectrum, and multidisciplinary discussion (MDD) helps in diagnosis. However, a subset remains unclassifiable, requiring histopathology for confirmation. This study assesses the agreement between clinicoradiological and histopathological diagnoses in such cases. Materials and Methods: A cross-sectional study was conducted at the Government Medical College, Kottayam. Of the 283 ILD patients screened, 35 ILD patients with an unclassifiable diagnosis after MDD underwent video-assisted thoracoscopic surgery or transbronchial lung biopsy. Agreement between MDD-based diagnosis and histopathology was analyzed using Cohen’s kappa coefficient. Results: Of the 35 patients, the mean age was 48.97 years. The most common MDD-based probable diagnoses were cryptogenic organizing pneumonia (22.9%), nonspecific interstitial pneumonia (17.1%), and hypersensitivity pneumonitis (14.3%). Biopsy findings confirmed the initial diagnosis in 88.57% of cases, with a kappa index of 0.739, indicating substantial agreement. Conclusion: Histopathological confirmation aligns well with MDD-based diagnosis, reinforcing the role of MDD in ILD assessment. However, a subset remains inconclusive, emphasizing the need for improved noninvasive diagnostic methods.